1. Field of the Invention
The present invention relates generally to caps having a storage means therein allowing the addition of adjuncts. More particularly, the present invention relates to a sanitary double cap allowing for the addition of an additive into the contents of a container with a relatively simple rotation of a predetermined portion of the double cap.
2. Description of the Related Art
Generally, a technique, in which medical powder or an adjunct, which have been stored in a cap of a container, is added into the container when the cap is pushed downwards, is well known. A representative example of this technique is shown in an illustration of a prior art shown in FIG. 1 through FIG. 3. As shown in FIG. 1, which is an exploded view of the prior art, contents are contained in a container, which has an open upper end. A lower cap 1 is coupled to an opening of a neck part of the container. The lower cap 1 includes an insertion part 3 which extends a predetermined length downwards from an upper end 2 of the lower cap 1 and defines an adjunct receiving chamber 4 therein. A thin film 5 forms a bottom of the insertion part 3 of the lower cap 1. A pipe body 6 of an upper cap 8 is fitted into the adjunct receiving chamber 4 of the lower cap 1. A frictional ring 7 is provided on a circumferential outer surface of the pipe body 6 of the upper cap 8.
To use the conventional cap, the upper cap, which has been in the state of FIG. 2, is pushed downwards. Then, as shown in FIG. 3, the thin film 5 that forms the bottom 11 of the insertion part 3 breaks, so that the adjunct 9, which has been in the pipe body 6 of the upper cap 8, is input into the container 12, thus forming a mixture 10.
This technique has an advantage of ease of addition of the adjunct 9. However, this technique is problematic in that, when it is desired for a user to use the mixture, it is not easy to open the lower cap 1.
Furthermore, because the state of the upper cap when pushed is not easily distinguished from the normal state of the upper cap, it is difficult for the user to determine whether the container has already been used or not.
As well, after the cap has been separated from the container and part of the mixture has been used, if the container is covered again with the cap to store remaining mixture, when the user desires to use the remaining mixture, it is not easy to open the cap, thus being inconvenient to the user.